/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
package org.apache.iotdb.db.mpp.plan.planner.plan.node.process;

import org.apache.iotdb.db.mpp.plan.planner.plan.node.PlanNode;
import org.apache.iotdb.db.mpp.plan.planner.plan.node.PlanNodeId;
import org.apache.iotdb.db.mpp.plan.planner.plan.node.PlanNodeType;
import org.apache.iotdb.db.mpp.plan.planner.plan.node.PlanVisitor;
import org.apache.iotdb.tsfile.utils.ReadWriteIOUtils;

import java.io.DataOutputStream;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.util.ArrayList;
import java.util.List;
import java.util.Objects;

public class SingleDeviceViewNode extends SingleChildProcessNode {

    private final String device;

    // To reduce memory cost, SingleDeviceViewNode doesn't serialize and deserialize
    // outputColumnNames.It just rebuilds using the infos from parent node.
    private final List<String> outputColumnNames;
    private final List<Integer> deviceToMeasurementIndexes;
    // For some isolated SingleDeviceViewNodes without parent node, they need to cache
    // the outputColumnNames themselves.
    private boolean cacheOutputColumnNames = false;

    public SingleDeviceViewNode(
            PlanNodeId id,
            List<String> outputColumnNames,
            String device,
            List<Integer> deviceToMeasurementIndexes) {
        super(id);
        this.device = device;
        this.outputColumnNames = outputColumnNames;
        this.deviceToMeasurementIndexes = deviceToMeasurementIndexes;
    }

    public SingleDeviceViewNode(
            PlanNodeId id,
            boolean cacheOutputColumnNames,
            List<String> outputColumnNames,
            String device,
            List<Integer> deviceToMeasurementIndexes) {
        super(id);
        this.device = device;
        this.cacheOutputColumnNames = cacheOutputColumnNames;
        this.outputColumnNames = outputColumnNames;
        this.deviceToMeasurementIndexes = deviceToMeasurementIndexes;
    }

    @Override
    public PlanNode clone() {
        return new SingleDeviceViewNode(
                getPlanNodeId(),
                cacheOutputColumnNames,
                outputColumnNames,
                device,
                deviceToMeasurementIndexes);
    }

    @Override
    public List<String> getOutputColumnNames() {
        return this.outputColumnNames;
    }

    public void setCacheOutputColumnNames(boolean cacheOutputColumnNames) {
        this.cacheOutputColumnNames = cacheOutputColumnNames;
    }

    public String getDevice() {
        return device;
    }

    public boolean isCacheOutputColumnNames() {
        return cacheOutputColumnNames;
    }

    public List<Integer> getDeviceToMeasurementIndexes() {
        return deviceToMeasurementIndexes;
    }

    @Override
    public <R, C> R accept(PlanVisitor<R, C> visitor, C context) {
        return visitor.visitSingleDeviceView(this, context);
    }

    @Override
    protected void serializeAttributes(ByteBuffer byteBuffer) {
        PlanNodeType.SINGLE_DEVICE_VIEW.serialize(byteBuffer);
        ReadWriteIOUtils.write(device, byteBuffer);
        ReadWriteIOUtils.write(cacheOutputColumnNames, byteBuffer);
        ReadWriteIOUtils.write(deviceToMeasurementIndexes.size(), byteBuffer);
        for (Integer index : deviceToMeasurementIndexes) {
            ReadWriteIOUtils.write(index, byteBuffer);
        }
        if (cacheOutputColumnNames) {
            ReadWriteIOUtils.write(outputColumnNames.size(), byteBuffer);
            for (String column : outputColumnNames) {
                ReadWriteIOUtils.write(column, byteBuffer);
            }
        }
    }

    @Override
    protected void serializeAttributes(DataOutputStream stream) throws IOException {
        PlanNodeType.SINGLE_DEVICE_VIEW.serialize(stream);
        ReadWriteIOUtils.write(device, stream);
        ReadWriteIOUtils.write(cacheOutputColumnNames, stream);
        ReadWriteIOUtils.write(deviceToMeasurementIndexes.size(), stream);
        for (Integer index : deviceToMeasurementIndexes) {
            ReadWriteIOUtils.write(index, stream);
        }
        if (cacheOutputColumnNames) {
            ReadWriteIOUtils.write(outputColumnNames.size(), stream);
            for (String column : outputColumnNames) {
                ReadWriteIOUtils.write(column, stream);
            }
        }
    }

    public static SingleDeviceViewNode deserialize(ByteBuffer byteBuffer) {
        String device = ReadWriteIOUtils.readString(byteBuffer);
        boolean cacheOutputColumnNames = ReadWriteIOUtils.readBool(byteBuffer);
        int listSize = ReadWriteIOUtils.readInt(byteBuffer);
        List<Integer> deviceToMeasurementIndexes = new ArrayList<>(listSize);
        while (listSize > 0) {
            deviceToMeasurementIndexes.add(ReadWriteIOUtils.readInt(byteBuffer));
            listSize--;
        }
        List<String> outputColumnNames = null;
        if (cacheOutputColumnNames) {
            int columnSize = ReadWriteIOUtils.readInt(byteBuffer);
            outputColumnNames = new ArrayList<>();
            while (columnSize > 0) {
                outputColumnNames.add(ReadWriteIOUtils.readString(byteBuffer));
                columnSize--;
            }
        }

        PlanNodeId planNodeId = PlanNodeId.deserialize(byteBuffer);
        return new SingleDeviceViewNode(
                planNodeId, cacheOutputColumnNames, outputColumnNames, device, deviceToMeasurementIndexes);
    }

    @Override
    public boolean equals(Object o) {
        if (this == o) {
            return true;
        }
        if (o == null || o.getClass() != getClass()) {
            return false;
        }
        if (!super.equals(o)) {
            return false;
        }
        SingleDeviceViewNode that = (SingleDeviceViewNode) o;
        return device.equals(that.device)
                && outputColumnNames.equals(that.outputColumnNames)
                && deviceToMeasurementIndexes.equals(that.deviceToMeasurementIndexes);
    }

    @Override
    public int hashCode() {
        return Objects.hash(super.hashCode(), device, outputColumnNames, deviceToMeasurementIndexes);
    }

    @Override
    public String toString() {
        return "SingleDeviceView-" + this.getPlanNodeId();
    }
}
